Most oil/water separators, including parallel plate separators, are based on static settling. The driving force is only the difference in specific gravity between the oil and the water. In the case of oil from tar sands, the specific gravity of the hydrocarbons at room temperature is higher than that of water and only near the boiling point of water is this situation reversed. Due to the limited available driving force because of the relatively low specific gravity differential in a tar sands oil/water system, there inherently are many problems associated with use of prior art separators in such a system, and accordingly the present invention is directed to overcoming this and other problems, as will be apparent hereinafter.